How It Works

Download Test

It begins with downloading the smallest sample size (128 KB). While it shows the real-time bandwidth graph, it also watches the download duration. If it takes less than eight seconds, next sample would be tried otherwise it continues with upload test. Among all downloaded samples only the last one which took more than eight seconds will be accepted and your download speed is actually based on the last sample file.

Upload Test

When the download test is completed, similar incremental mechanism will be used to send back data to SpeedOf.Me test server. The upload test starts with a smaller sample file and will gradually increase until it takes more than 8 seconds to upload a sample file.

Note:
If you are behind a proxy server or firewall, you may experience problems with upload test. It may not work well or it may give you inaccurate results. In these cases you should use another browser as different browsers react differently regarding this issue.

Smart Test Method

In order to guarantee that your Internet connection is tested thoroughly, SpeedOf.Me tests your bandwidth in several passes. Sample file sizes increase gradually until it takes longer than eight seconds to download the sample file. As a result, SpeedOf.Me unlike other speed tests, is able to measure connection speeds in a wide range. From a slow 10 Kbps Mobile GPRS to a very fast 100 Mbps cable user (or even higher) automatically.
Sample files are in these sizes:
128 KB, 256 KB, 512 KB, 1, 2, 4, 8, 16, 32, 64 and 128 MB.

Test Servers

SpeedOf.Me hosts its sample files on CDN. It benefits from 88 (and counting) super servers called PoP. Each PoP may utilize several servers. They are located in various places around the world near primary Internet exchange points. These super servers have a massive computing and caching power and are directly connected to all the major backbone networks.
When the test is started, the quickest and most reliable server, not necessarily the nearest, would be chosen. There are many factors involved in selecting the best test server for you. However, it is done automatically using CDN technology to ensure the best testing quality. Here are SpeedOf.Me PoP locations:

Accuracy

Unlike other speed tests that require third party applications (plugins), SpeedOf.Me tests your Internet speed directly from your web browser not through Flash or Java Plug-ins with lots of overhead.

SpeedOf.Me also downloads large contiguous sample files. This is what you usually do when downloading a webpage or media. This is while other speed test services download small chunks in parallel and do heavy adjustments to calculate your approximate speed.

SpeedOf.Me utilizes several test servers (PoPs) in various locations which makes the test result more realistic. Other speed test services have a different approach about test server location. Some choose the nearest physical test server, probably inside your ISP. It seems illogical because the speed between you and the selected server is always higher than your real speed [for connecting] to the rest of the Internet.
On the other hand, some speed test services use a single test server to test users' connection speed in all geographical locations. For example, imagine a user is in Asia or Australia while the test server is in the US. The result would be inaccurate again because the end user is very far away from the testing server.
All of these make SpeedOf.Me the most accurate and realistic speed test among others.

Which browser is better?

Generally speaking, the more HTML5 features the browser supports the more precise the test result would be.
Our recommended browsers are latest version of Chrome, Firefox or Safari.
If you are using Internet Explorer, please be advised that the upload progress may not be shown in some older versions of IE. So, please be patient while the upload test is in progress.